Area Forecast Discussion
Issued by NWS La Crosse, WI

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FXUS63 KARX 181111
AFDARX

Area Forecast Discussion
National Weather Service La Crosse WI
510 AM CST Wed Jan 18 2017

.SHORT TERM...(Today through Thursday Night)
Issued at 243 AM CST Wed Jan 18 2017

Surface map early this morning has a ridge of high pressure extending
from KS/MO northward through eastern MN/western WI. Light winds and
very moist boundary later has led to widespread fog and stratus
across our area. So far, just pockets of dense fog here and there
which we have covered with a special weather statement. Clouds and
fog were keeping temperatures relatively mild for mid-
January...mostly in the upper 20s to lower 30s as of 2 am.

For today...will have to contend with stratus and fog early on, but
then expecting skies to become mostly sunny by afternoon as drier
Plains air advects in on southwest winds and helps scour out the
boundary layer. Look for highs today in the 35 to 40 degree range.

Very moist lower boundary layer for tonight with light southerly
winds. This will likely lead to stratus/fog development overnight.
May have to watch again for some locally dense fog. Otherwise...plan
on overnight lows in the middle 20s to the lower 30s.

For Thursday into Thursday night...will be watching a mid-
level/surface trough rotate northeast out of the Central Plains
toward the region. This will bring a chance of rain into northeast
IA/far southwest WI in the afternoon. Otherwise, looking mild with
highs topping off in the upper 30s/lower 40s. Thursday night looking
wet as the system moves closer. Looks like mainly rain, but may see
some patches of freezing rain as well as temperatures bottom out in
the lower/middle 30s.

.LONG TERM...(Friday through Tuesday)
Issued at 243 AM CST Wed Jan 18 2017

Friday will continue to see the likelihood of rain mainly east of the
Mississippi River, with perhaps a bit of a wintry mix of sleet and
light snow as well at times, as that mid-level wave moves through
the area. Some sleet or light snow may mix in at times across
central WI as the column cools. Look for highs in the middle 30s to
the lower 40s.

On/off generally light precipitation chances will be seen through
the weekend and into early next week as a couple more troughs rotate
northeast through the region. Relatively mild temperatures continue
though with highs in the 40s over the weekend and the upper
30s/lower 40s Monday an Tuesday.

&&

.AVIATION...(For the 12Z TAFS through 12Z Thursday morning)
Issued at 510 AM CST Wed Jan 18 2017

Low stratus has held fast for the overnight hours...but western edge
making some progress toward KRST, while bufkit soundings suggest it
will start to mix and breakout by 18z. Will push trends this way.
Vsbys have improved as the winds have picked up from the south.

Expect generally sct/skc conditions then the rest of the day into
tonight. Models adamant on a fog and/or stratus threat later
tonight...pooling low level moisture under the inversion. South
winds could keep it stirred though, and not much snow pack to work
on south of the TAF sites. That said, daytime melting will certainly
help in moistening the boundary layer. Going to introduce some mvfr
vsbys overnight for now, but may need to lower those more over the
next few forecast cycles.

&&

.ARX WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
IA...None.
&&

$$

SHORT TERM...DAS
LONG TERM....DAS
AVIATION.....Rieck



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